Heat exchanger

ABSTRACT

A heat exchanger, in particular a heat exchanger for a motor vehicle, which is constructed from modular heat exchanger components can include the following types of heat exchanger components: a plurality of tubes, in particular flat tubes, a plurality of plates and at least one connecting piece having an inlet opening for introducing a fluid and/or an outlet opening for discharging the fluid, the outer contour of the heat exchanger being at least partially formed by the outer contours of the heat exchanger components, the reliable arrangement of the same type of heat exchanger component in the designated location within the heat exchanger is reliably guaranteed. Thus, the heat exchanger components of the same type have different outer contours which form an outer contour of the heat exchanger so that heat exchanger components of the same type but having different functions may be distinguished from each other on the basis of their different outer contours.

This nonprovisional application claims priority under 35 U.S.C. §119(a)to German Patent Application No. DE 10 2008 053 308.4, which was filedin Germany on Oct. 27, 2008, and which is herein incorporated byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a heat exchanger and to a method formanufacturing a heat exchanger. The invention also relates to a motorvehicle air conditioning system and a motor vehicle.

2. Description of the Background Art

Heat exchangers are used to transfer heat from one fluid to anotherfluid. For example, heat is transferred from a cooling liquid to theambient air by a heat exchanger. This is used, in particular, in motorvehicles, in which the heat exchanger is used to discharge the wasteheat released by the internal combustion engine into the ambient air.The heat exchanger generally includes two manifolds between which aplurality of tubes are arranged. Furthermore, heat exchangers may beused in motor vehicles in order, for example, to cool motor ortransmission oil or air, for example charge air, or they may be used tocool a refrigerant in air conditioning systems for motor vehicles, i.e.the heat exchanger acts as a condenser within a refrigerant circuit.

Different manufacturing methods are know for manufacturing heatexchangers. In the so-called modular design, different heat exchangercomponents are assembled into a heat exchanger in a core builder. Theheat exchanger components are generally flat tubes, plates with andwithout openings as well as two connecting pieces in which an inletopening and an outlet opening for the fluid are provided. Turbulenceinserts are generally arranged in the flat tubes, and the ends of theflat tubes are each closed by an insert part. Recesses are provided inthe area of the ends of the flat tubes. The plates having openings thatare placed on the end area of each flat tube. The recesses in the flattubes are covered by the openings in the plates. A flat tube is againplaced on both plates, and this process continues to repeat until therecesses and openings form a manifold of the heat exchanger. The flattube includes a top and bottom wall, in each of which the recess isprovided in the end area. The fluid may flow into the flat tube betweenthe top and bottom walls. The fluid flows into the flat tubes from themanifold formed by the recesses and openings.

The plates also perform different functions as a type of heat exchangercomponent. For example, a plate without an opening may be provided witha vertical threaded bore. In addition, horizontal threaded bores, forexample, may be provided at different points on the plates havingopenings. The threaded bores are used, for example, to fasten the heatexchanger to the body of a motor vehicle or to fix other components tothe heat exchanger via the threaded bores. One type of heat exchangercomponent, i.e. a plate, thus has different functions.

In manufacturing the heat exchanger, the individual plates are eachplaced on the flat tubes. Errors may arise if the wrong plates, i.e. theplates having an incorrect function, are placed in the wrong locationwithin the heat exchanger. This results in considerable damage becausethe heat exchanger is generally no longer suitable for its usualapplication if the error is not detected, or if a portion of an alreadyassembled heat exchanger must be removed in a costly and time-consumingmanner if the incorrect stacking of the plates is detected duringmanufacture, in particular while the plates and the flat tubes are beingarranged.

EP 0 961 095 B1, which is incorporated herein by reference, shows ageneric heat exchanger. An outer contour of the plates forms an outercontour of the heat exchanger. However, the outer contours of all platesare identical, making it impossible to distinguish between differentplates on the basis of the outer contour.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to reliably guaranteethat a single type of heat exchanger component is reliably arranged inits designated location within the heat exchanger in the case of a heatexchanger, a motor vehicle air conditioning system, a motor vehicle anda method for manufacturing a heat exchanger. During manufacture, theheat exchanger and the motor vehicle air conditioner as well as themotor vehicle should be able to perform the provided functionseconomically and during operation. In addition, it should be possible tocarry out the method for manufacturing the heat exchanger easily andeconomically.

This object is achieved by a heat exchanger for a motor vehicle whichcan be constructed from modular heat exchanger components, including thefollowing types of heat exchanger components: a plurality of tubes, inparticular flat tubes, a plurality of plates and at least one connectingpiece having an inlet opening for introducing a fluid and/or an outletopening for discharging the fluid, the outer contour of the heatexchanger being at least partially formed by the outer contours of theheat exchanger components, heat exchanger components of the same typehaving different outer contours which form an outer contour of the heatexchanger, so that heat exchanger components of the same type, inparticular those having different functions, are distinguishable bytheir different outer contours. In the case of different functions, theheat exchanger components have different outer counters which also forman outer contour of the heat exchanger. This makes it possible todistinguish between heat exchanger components of the same type based onthe geometry of the outer contour.

In particular, the heat exchanger components of the same type having thedifferent outer contours have different functions or properties.

In a further embodiment, the plates can be designed with or withoutopenings. Plates with openings are used to form a manifold within theheat exchanger by stacking plates with openings on top of each other.Plates without openings are generally arranged on the top and bottomends of the heat exchanger in order to close the manifold formed by theplates with openings and recesses in tubes, in particular flat tubes.

In a further embodiment, a closing member is arranged on a first, e.g.upper, and preferably also on a second, e.g. lower, end of the heatexchanger.

The different outer contours can be formed by at least one projectionand/or at least one recess.

In a further variant, the at least one projection and/or the at leastone recess can have/has a rectangular cross section. In particular, theat least one projection and/or the at least one recess is/are alsodesigned with a square cross section. In addition, the at least oneprojection and/or the at least one recess may also have the shape of aknob, a cone or a part of a cone.

A recess can be suitably provided in the area of an end of the tubes.

In a further embodiment, a partial section of the tubes can be arrangedbetween the plates in the area of the end of the tubes, and the openingsin the plates can at least partially cover the recesses in the flattubes, so that the openings and the recesses form a manifold.

In particular, turbulence inserts are provided in the tubes and/or theends of the tubes are closed by an insert part.

In a further embodiment, the surface of the heat exchanger components,in particular the plates, flat tubes and connecting pieces as well asthe closing members can be solder-plated. This enables the heatexchanger components joined to form a structural unit to be soldered ina furnace at temperatures of, for example, 600° C., thereby enabling theheat exchanger components to be connected to each other in a fluid-tightmanner.

In a method according to the invention, heat exchangers are manufacturedin a modular design from heat exchanger components, using, for example,the following steps: producing heat exchanger components, includingtubes, plates and at least one connecting piece, in particular at leasttwo connecting pieces; arranging the heat exchanger components into astructural unit; establishing a fluid-tight connection between the heatexchanger components contained in the structural unit, heat exchangercomponents of the same type having different outer contours which forman outer contour of the heat exchanger, so that when the different typesof heat exchanger components are arranged into a structural unit, heatexchanger components of the same type having different functions may bedistinguished from each other by a test component on the basis of theirdifferent outer contours to avoid incorrect arrangement of heatexchanger components of the same type having different functions.

The test component can be a mechanical component whose surface orgeometry has a complementary design in relation to the outer contours orgeometries of the heat exchanger components. As a result, when arrangingthe heat exchanger components, which is generally carried out bystacking the components in a core builder, e.g. manually,semi-automatically or automatically, the heat exchanger components whichare arranged in a location other than the designated one have a positionother than the designated one. The heat exchanger components aregenerally stacked on an inclined table. A heat exchanger component ofthe same type which performs a different function thus occupies adifferent position when arranged in a location other than its designatedone. This other position may be detected and the heat exchangercomponent then replaced by a heat exchanger component of the correcttype. Production errors are avoided thereby. Moreover, the testcomponent may also detect or scan the surface or geometry, i.e. theouter contours of the heat exchanger components, in a different manner,e.g. optically, electrically or magnetically. The location of a heatexchanger component is thus determined by the construction plan of theheat exchanger component. An incorrect position of the heat exchangercomponent is determined by an arrangement of the heat exchangercomponent in the non-designated, i.e. incorrect, location.

In a further embodiment, a plate can be arranged between two tubes, inthe area of an end of the tubes in each case.

In an embodiment, two plates can be laid on one tube.

In a further embodiment, the plates can be provided with openings, andrecesses can be provided in the tubes in the area of one end of thetube, and when the tubes and plates are arranged, the openings andrecesses at least partially cover each other.

In a further embodiment, corresponding sections of the test componenthave a shape which is complementary to the type of heat exchangercomponent provided in this position, so that when a type not designatedfor this position is arranged therein, the incorrect type of heatexchanger component occupies a different location that the designatedheat exchanger component.

In an additional embodiment, the position of the different types of heatexchanger components is detected, for example, by a monitoring sensorwhen the heat exchanger components are arranged, and if a type of heatexchanger component assumes a non-designated position duringarrangement, an error message occurs or the manufacturing method isterminated and/or the non-designated type of heat exchanger component isreplaced by the designated type of heat exchanger component. Themonitoring sensor may be, for example, an optical and/or a mechanicaland/or an electrical monitoring sensor. In addition, the location of theheat exchanger components may also be checked by operators if a manualcore builder is used.

In a further embodiment, the positions of the different types of heatexchanger components are detected, for example, by an operator, inparticular visually, when the heat exchanger components are arranged,and if a type of heat exchanger component assumes a non-designatedposition, an error message occurs or the manufacturing method isterminated and/or the non-designation type of heat exchanger componentis replaced by the designated type of heat exchanger component.

In manufacturing the heat exchanger, the individual heat exchangercomponents are arranged into a structural unit. This is generallycarried out by stacking the individual heat exchanger components on atable in a core builder. After the individual heat exchanger componentshave been assembled into a structural unit, they are pressed togetherunder pretension in a clamping apparatus. The surfaces of the individualheat exchanger components are provided with solder, i.e. they aresolder-plated. The pretensioned structural unit is subsequently heatedto temperatures in the range of approximately 600° C. in a solderingfurnace. The individual heat exchanger components are soldered togetherthereby, connecting them to each other in a fluid-tight manner. Acooling liquid or air, for example, is used as the fluid.

A motor vehicle air conditioning system or a motor vehicle includes theheat exchanger described in this application.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus, are not limitiveof the present invention, and wherein:

FIG. 1 shows a schematic, perspective and partially cut-away view of aheat exchanger;

FIG. 2 shows a schematic, perspective view of a plate without arepresentation of the special outer contour;

FIG. 2 a shows a perspective view of the plate without an opening, buthaving a vertical threaded bore in a first embodiment;

FIG. 2 b shows a perspective view of the plate with an opening andhaving a front horizontal threaded bore in a second embodiment;

FIG. 2 c shows a perspective view of the plate with an opening andhaving a rear horizontal threaded bore in a third embodiment;

FIG. 2 d shows a perspective view of the plate without an opening in afourth embodiment;

FIG. 2 e shows a perspective view of the plate with an opening in afifth embodiment;

FIG. 3 shows a perspective partial view of a flat tube;

FIG. 4 shows a perspective view of a connecting piece;

FIG. 5 shows a cross-sectional view V-V according to FIG. 4, includingthe flat tube; and

FIG. 6 shows a cross-sectional view VI-VI according to FIG. 3.

DETAILED DESCRIPTION

FIG. 1 shows a schematic, perspective and partially cut-away view of aheat exchanger 1. Heat exchanger 1 is used to cool a cooling liquid forthe internal combustion engine of a motor vehicle, and an air flow 16,whose flow direction is marked by the arrow, flows through the heatexchanger for this purpose.

Tubes 3 designed as flat tubes 4, between which wavy fins 13 areprovided, are stacked in heat exchanger 1. Wavy fins 13 are used, on theone hand, to mechanically connect flat tubes 4 to each other, and alsoto elevate the surface of heat exchanger 1 in order to thereby improvethe cooling capacity. A recess 5 is provided at an end 10 of flat tubes4 (FIG. 3). Flat tube 4 includes a top wall 20, a bottom wall 21 and twoside walls 22. Top wall 20 and bottom wall 21 are positioned a shortdistance above one another and connected to each other by the two curvedside walls 22. Recess 5 is thus present in both top wall 20 and bottomwall 21. In the area of recess 5 of flat tube 4, a fluid may thus flowinside flat tube 4 between top wall 20 and bottom wall 21. End 10 offlat tube 4 is closed in a fluid-tight manner by an insert part 12(FIGS. 3 and 6). A turbulence insert 11 is provided inside flat tube 4.Turbulence insert 11 has a fin-like design and generates a turbulentflow inside the flat tube by mixing the cooling liquid. When fluid isflowing through flat tube 4, the latter largely has the same temperatureon its surface, thereby increasing the cooling capacity of heatexchanger 1.

In addition to flat tubes 4, plates 6 are also provided in heatexchanger 1 as different types of heat exchanger components 2. Plates 6are provided with an opening 7 (FIG. 2). Within heat exchanger 1, oneplate 6 is provided between two flat tubes 4 in the area of end 10 offlat tube 4. In the interest of simplicity, FIG. 1 shows only heatexchanger components 2 in the upper and lower areas. Plates 6 stacked inheat exchanger 1 and having openings 7 as well as flat tubes 4 havingrecesses 5 thus form a manifold with the aid of recesses 5 and openings7.

In addition, a connecting piece 8 is present in the upper and lowerareas of heat exchanger 1. Lower connecting piece 8 has an outletopening 15 and upper connecting piece 8 has an inlet opening (notillustrated). The cooling liquid is introduced into the inlet openingfor cooling purposes, and the cooled cooling liquid is discharged fromheat exchanger 1 via outlet opening 15. Connecting piece 8 is providedwith a slot 17 (FIG. 5), in which a flat tube 4 is arranged in eachcase. Connecting pieces 8 also have an opening 7 (FIG. 5). Opening 7 inconnecting piece 8 is thus also used to form the manifold within heatexchanger 1. Instead of arranging the two connecting pieces on the upperleft and lower left sides of heat exchanger 1, it is possible, forexample, to arrange a first connecting piece 8 on the lower left sideand a second connecting piece 8 on the upper right side of heatexchanger 1 (not illustrated).

The upper and lower ends of heat exchanger 1 are sealed by a connectingpart 14. Connecting part 14 is thus connected to a plate 6, a connectingpiece 8 and wavy fin 13. Flat tube 4, plates 6, connecting pieces 8,insert parts 12, wavy fins 13 and closing members 14 are heat exchangercomponents 2 of heat exchanger 1. Heat exchanger 1 is manufactured fromthese heat exchanger components 2 in a core builder.

Plates 6 as an equivalent type of heat exchanger component 2 may performdifferent functions for heat exchanger 1. For example, plates 6 may alsobe designed without an opening 7 (FIGS. 2 a and 2 d). A plate 6 withoutan opening 7 may be provided, for example, with a vertical threaded bore18 (FIG. 2 a). In addition, plates 6 having an opening 7 may be providedwith a horizontal threaded bore in different locations (FIGS. 2 b, 2 c).Plates 6 with and without a recess may also be provided without avertical or horizontal threaded bore 18, 19 (FIGS. 2 d and 2 e).Threaded bores 18, 19 are used to attach heat exchanger 1 to a body ofthe motor vehicle or to fix other components to heat exchanger 1.

The same type of heat exchanger component 2, i.e. plate 6, thus has adifferent function for heat exchanger 1. In manufacturing heat exchanger1 in the core builder, individual plates 6 must be stacked. Plates 6having the different functions, in particular also a function without anadditional fixing means according to plates 6 in FIGS. 2 d and 2 e, havea different outer contour 9. Outer contour 9 is formed by projections 23and recesses 24, which have a largely rectangular cross section (FIGS. 2a and 2 e). When individual plates 6 are stacked in the core builder(not illustrated), different plates 6 according to FIGS. 2 a through 2 emay be placed in the incorrect location. The core builder is providedwith a test component (not illustrated). The test component has a shapeor geometry which is complementary to outer contour 9 of plates 6. If anincorrect plate 6 is inserted, incorrect plate 6 assumes a differentposition on a table of the core builder. In each case, the testcomponent is designed for a specific heat exchanger 1. The fivedifferent plates 6 used each have different outer contours 9. Thecorresponding section of the test component has a complementary designin relation to outer contour 9 of plate 6 provided in this location. Ifan incorrect plate 6 is placed in this position, plate 6 is unable topenetrate far enough into the test component because the complementaryshape of the test component prevents it from doing so. All plates 6 havethe same length. This means that an incorrect plate 6 sticks out fromthe other plates 6 when manufacturing heat exchanger 1 on a core buildertable. This is both manually detectable by an operator and automaticallydetectable by a monitoring sensor, and the manufacturing method may beeither terminated automatically or the operator may replace incorrectplate 6 with correct plate 6 designated for this location.

From an overall perspective, heat exchanger 1 according to the inventionand the method according to the invention for manufacturing a heatexchanger 1 are associated with considerable advantages. Productionerrors due to incorrectly arranged plates 6 or heat exchanger components2 may be easily avoided during the manufacture of heat exchanger 1.Different outer contours 9 of heat exchanger components 2 make itpossible to easily detect the arrangement of heat exchanger components 2of the same type but having different functions in the incorrectlocation within heat exchanger 1 during manufacture. Errors duringmanufacture may be avoided thereby and the costs of heat exchanger 1 aswell as the costs of the method for manufacturing heat exchanger 1 maybe reduced.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are to beincluded within the scope of the following claims.

1. A heat exchanger formed of modular heat exchanger components,comprising: a plurality of tubes; a plurality of plates; and at leastone connecting piece having an inlet opening configured to introduce afluid and/or an outlet opening configured to discharge the fluid, anouter contour of the heat exchanger being at least partially formed byouter contours of the heat exchanger components, wherein the modularheat exchanger components of the same type have different outer contoursthat form the outer contour of the heat exchanger such that heatexchanger components of the same type are distinguished from each otherbased on their different outer contours.
 2. The heat exchanger accordingto claim 1, wherein the heat exchanger components of the same type, buthaving different outer contours, are configured to function differently.3. The heat exchanger according to claim 1, wherein the plates areconfigured with or without openings.
 4. The heat exchanger according toclaim 1, wherein the different outer contours are formed by at least oneprojection and/or at least one recess.
 5. The heat exchanger accordingto claim 4, wherein the at least one projection and/or the at least onerecess have/has a rectangular cross section.
 6. The heat exchangeraccording to claim 1, wherein a recess is provided in an area of one endof the tubes.
 7. The heat exchanger according to claim 6, wherein apartial section of the tubes is arranged between the plates in the areaof the end of the tubes, and wherein the openings in the plates at leastpartially cover the recesses in the flat tubes such that the openingsand the recesses form a manifold.
 8. The heat exchanger according toclaim 1, wherein turbulence inserts are provided in the tubes and/orends of the tubes are closed by an insert part.
 9. A method formanufacturing a heat exchanger from heat exchanger components in amodular design, the method comprising: providing heat exchangercomponents having tubes, plates and at least one connecting piece;arranging the heat exchanger components into a structural unit; andestablishing a fluid-tight connection between the heat exchangercomponents contained in the structural unit, wherein the heat exchangercomponents of the same type have different outer contours that form anouter contour of the heat exchanger such that when the different typesof heat exchanger components are arranged into a structural unit a testcomponent distinguishes between heat exchanger components of the sametype that have different functions based on the different outer contoursto avoid incorrect arrangement of heat exchanger components of the sametype having different functions.
 10. The method according to claim 9,wherein a plate is arranged between two tubes in an area of an end ofthe tubes.
 11. The method according to claim 9, wherein two plates areplaced on one tube.
 12. The method according to claim 9, whereincorresponding sections of the test component have a shape that iscomplementary to the outer contour of the type of heat exchangercomponent designated for this location so that when a type of heatexchanger component not designated for this position is arrangedtherein, the non-designated type of heat exchanger component assumes adifferent position than the designated heat exchanger component.
 13. Themethod according to claim 12, wherein the positions of the differenttypes of heat exchanger components are detected by a monitoring sensorwhen the heat exchanger components are arranged, and if a type of heatexchanger component assumes a non-designated position duringarrangement, an error message occurs and/or the manufacturing method isterminated and/or the non-designated type of heat exchanger component isreplaced by the designated type of heat exchanger component.
 14. Themethod according to claim 12, wherein the positions of the differenttypes of heat exchanger components are detected visually by an operatorwhen the heat exchanger components are arranged, and if a type of heatexchanger component assumes a non-designated position, the manufacturingmethod is terminated and/or the non-designated type of heat exchangercomponent is replaced by the designated type of heat exchangercomponent.
 15. A motor vehicle air conditioning system or a motorvehicle, wherein the motor vehicle air conditioning system or motorvehicle includes a heat exchanger according to claim
 1. 16. The heatexchanger according to claim 1, wherein the heat exchanger is a motorvehicle heat exchanger.
 17. The heat exchanger according to claim 1,wherein the tubes are configured as flat tubes.